The present invention concerns drinking cups, and more particularly concerns a cap having a valve for controlling fluid flow from and back into a drinking cup.
Drinking cups for young children often include a cap with an apertured spout and a valve to prevent fluid from being spilled. However, traditional valved youth drinking cups are difficult and/or time consuming to clean such that the valve can potentially become unsanitary and/or not fully functional. This problem is compounded by the fact that some mothers forget or are too busy to spend the time necessary to thoroughly clean the valve, or do not realize how important a thorough cleaning is. Another problem is that, in many existing cups having valves, it is difficult to tell if or when their valve(s) is properly cleaned, particularly when the valve is positioned inside of a concave region in their cap where it is difficult to see and reach. There are also numerous additional functional requirements that are difficult to achieve simultaneously. For example, the valve must be fast acting in order to prevent spillage, yet must allow fluid to flow easily out the spout to a young child using the drinking cup. Also, the drinking cup must reliably prevent leakage, yet must also operate equally well at multiple angles. Also, it is preferable that the valve allow fluid still in the spout to redrain back into the drinking cup so that small spills do not occur. In the cost competitive industry of products for young children, the drinking cup must be mechanically non-complex with a minimum number of pieces to minimize cost. Where the cap and valve can be disassembled, the loose pieces must be large enough to prevent them from being lost and to allow easy reassembly, yet must fit into and operate in the relatively small interior of a cup sized for a young user. Further, the reassembly procedure must be apparent from the parts themselves.
Some known drinking cups have a cap that includes a first valve to control fluid flow out of the spout, and a second valve to control air flow into the drinking cup. However, this valving arrangement increases the number of pieces, doubles the sanitation and misfunction problems, and adds significant expense to the product. Another problem is that these known valving arrangements do not work properly if either of the valves becomes plugged or partially inoperative, which is more likely to occur with two valves than with a single valve.
Silicon rubber valves are known that can be used for dispensing food in a controlled manner. Several such valves are shown in U.S. Pat. Nos. 5,439,143 and 5,409,144 and patents related thereto. However, the silicon material can be difficult to retain in place since it is generally not possible to glue or adhere it to a surface. Further, the valve requires room to operate, which can be a problem in a youth-sized drinking cup located inside of a spout on a cap. Also, sanitation and/or replacement of non-functional valves continues to be problematic.
Accordingly, an apparatus solving the aforementioned problems is desired.